Abstract
A procedure is described that results in a substantial increase in signal intensity and in improved accuracy of positive-ion mass calibration when using commercially available kits of monodisperse dendrimers (SpheriCal®) in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS). The peak intensities are amplified by an admixture of 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene] malononitrile (DCTB) matrix to the kits comprising of 9-nitroanthracene matrix, sodium trifluoroacetate, and four dendrimers. Boosted ion formation then permits lower laser fluence to be used and thus yields enhanced mass resolution. Further, the number of reference peaks is doubled by doping the sample preparation with cesium ions. This results in four [M+Cs]+ ion signals in addition to four [M+Na]+ ion signals provided by the standard kit. Overall, the modified procedure notably reduces the consumption of the expensive calibration standard kits, while it increases mass resolution and enables the use of an advanced calibration algorithm requiring at least six reference peaks.
Similar content being viewed by others
References
Hillenkamp F, Peter-Katalinic J, editors. MALDI MS: a practical guide to instrumentation, methods and applications. Weinheim: Wiley-VCH; 2013.
Dreisewerd K. Recent methodological advances in MALDI mass spectrometry. Anal Bioanal Chem. 2014;406(9–10):2261–78. doi:10.1007/s00216-014-7646-6.
Zhang G, Presly O, White F, Oppel IM, Mastalerz M. A shape-persistent quadruply interlocked giant cage catenane with two distinct pores in the solid state. Angew Chem Int Ed. 2014;53(20):5126–30. doi:10.1002/anie.201400285.
Zhang G, Mastalerz M. Organic cage compounds—from shape-persistency to function. Chem Soc Rev. 2014;43(6):1934–47. doi:10.1039/c3cs60358j.
Karas M, Gluckmann M, Schäfer J. Ionization in matrix-assisted laser desorption/ionization: singly charged molecular ions are the lucky survivors. J Mass Spectrom. 2000;35(1):1–12. doi:10.1002/(SICI)1096-9888(200001)35:1<1::AID-JMS904>3.0.CO;2-0.
Gruendling T, Sauerland V, Barahona C, Herz C, Nitsch U. Polyalanine—a practical polypeptide mass calibration standard for matrix-assisted laser desorption/ionization mass spectrometry and tandem mass spectrometry in positive and negative mode. Rapid Commun Mass Spectrom. 2016;30(6):681–3. doi:10.1002/rcm.7492.
Lou X, van Dongen JLJ, Meijer EW. Generation of CsI cluster ions for mass calibration in matrix-assisted laser desorption/ionization mass spectrometry. J Am Soc Mass Spectrom. 2010;21(7):1223–6. doi:10.1016/j.jasms.2010.02.029.
Mochizuki S. Enhanced measurement of CsI cluster ions for mass calibration in MALDI-MS using sugar alcohols. Anal Methods. 2015;7(5):2215–8. doi:10.1039/c4ay02509a.
Grayson SM, Myers BK, Bengtsson J, Malkoch M. Advantages of monodisperse and chemically robust “spherical” polyester dendrimers as a “universal” MS calibrant. J Am Soc Mass Spectrom. 2014;25(3):303–9. doi:10.1007/s13361-013-0777-8.
Casey BK, Grayson SM. Letter: the potential of amine-containing dendrimer mass standards for internal calibration of peptides. Eur J Mass Spectrom. 2015;21(5):747–52. doi:10.1255/ejms.1394.
Montaudo G, Montaudo MS, Puglisi C, Samperi F. Self-calibrating property of matrix-assisted laser desorption/ionization time-of-flight spectra of polymeric materials. Rapid Commun Mass Spectrom. 1994;8(12):981–4. doi:10.1002/rcm.1290081215.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
No humans or animals were involved in this study.
Conflict of interest
The author declares that he has no conflict of interests.
Electronic supplementary material
Below is the link to the electronic supplementary material.
ESM 1
(PDF 946 kb)
Rights and permissions
About this article
Cite this article
Gross, J.H. Improved procedure for dendrimer-based mass calibration in matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry. Anal Bioanal Chem 408, 5945–5951 (2016). https://doi.org/10.1007/s00216-016-9714-6
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00216-016-9714-6